This is a working overview of somatotroph, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-08-26 and is reviewed periodically as new material appears.
Tesamorelin is a synthetic peptide built from 44 amino acids and classified with the growth hormone–releasing hormone family. Its sequence corresponds to the human GHRH(1-44) backbone, carrying one structural change at the amino terminus. That change is a trans-3-hexenoyl group placed where the natural peptide would have an unmodified end. The modification is the feature that separates the compound from the endogenous hormone in name, in stability, and in how it is handled in the laboratory.
The hexenoyl cap slows the enzyme step that trims the amino terminus of native GHRH, the same step that shortens its active lifetime in circulation. As a result, the modified peptide persists longer in plasma than the unmodified hormone in side-by-side comparison. Receptor activity stays broadly comparable, because the added group sits away from the residues that contact the binding site. This combination, preserved receptor activity with reduced degradation, explains why the analog was developed instead of the native sequence.
Several compounds share the GHRH framework, including sermorelin, the shorter 1-29 fragment, and other analogs built on the full 1-44 chain. Naming follows a common convention: a stem that identifies the peptide plus a suffix marking analog status. Reports may describe tesamorelin by its sequence fragment, as a GHRH(1-44) analog, or by its amino-terminal modification. Indexing the compound therefore requires searching all of these forms, since some older literature predates the current international nonproprietary name.
After injection, the peptide binds receptors on somatotroph cells in the anterior pituitary. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone into the bloodstream. Because the compound works through the body's own regulatory system, growth hormone pulses retain much of their normal feedback control. Repeated administration also raises insulin-like growth factor 1, a hormone produced mainly in the liver. Investigators treat that rise as a marker that the pituitary axis has been engaged.
Clinical study of tesamorelin has centered on adults with HIV-associated lipodystrophy, a condition in which abdominal fat accumulates while peripheral fat is lost. In controlled trials, treated participants showed reductions in visceral adipose tissue measured by imaging, alongside modest shifts in some lipid values. Effects on subcutaneous fat were smaller and less consistent across studies. Whether these changes translate into fewer cardiovascular events remains an open question, because the trials were not designed or powered to answer it.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic peptide | GHRH analog family |
| Residue count | 44 amino acids | Matches human GHRH(1-44) backbone |
| N-terminal group | trans-3-hexenoyl | Main structural difference from native hormone |
| Appearance | White to off-white powder | Lyophilized solid form |
| Solubility class | Freely soluble in water | Peptide character; less soluble in organic solvents |
Tesamorelin occupies a narrow position among agents that act on the growth hormone axis. Unlike growth hormone itself, which is given as replacement, it stimulates the pituitary to release the hormone in pulses, so the downstream increase in insulin-like growth factor 1 depends on intact somatotroph function. Other peptides in the same family include shorter GHRH fragments and synthetic secretagogues with different stability profiles. Several points remain unresolved, including whether the reduction in visceral fat translates into fewer cardiovascular events, what happens to metabolic markers after long-term use, and how the drug compares with lifestyle or surgical approaches.
Tesamorelin is a synthetic peptide that belongs to the growth hormone-releasing hormone family and contains the same forty-four amino acid sequence as endogenous GHRH, extended at the amino terminus by a trans-3-hexenoyl group. That small fatty acid modification protects the peptide from rapid cleavage by dipeptidyl peptidase-4, the enzyme that shortens the half-life of native GHRH to only a few minutes. Chemically the compound is produced by solid-phase peptide synthesis, purified by chromatography, and supplied as a sterile lyophilized powder for reconstitution.
Regulatory approval in the United States came in 2010, when the Food and Drug Administration cleared the peptide for the reduction of excess abdominal fat in adults with HIV infection and associated lipodystrophy. The decision rested mainly on two randomized phase 3 trials that enrolled roughly eight hundred patients and ran for twenty-six weeks. Participants receiving active drug showed substantially greater declines in visceral adipose tissue than those receiving placebo, while total body weight changed comparatively little. A reformulated presentation was later approved, and the product has remained a niche therapy rather than a general weight-loss agent.
Binding of tesamorelin to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and the release of growth hormone into circulation. Because the peptide acts upstream of the growth hormone axis, its effects are partly mediated by hepatic insulin-like growth factor 1 (IGF-1) production. The pulsatile character of endogenous growth hormone secretion is preserved rather than replaced. Whether amplified signaling produces effects beyond those of native GHRH remains an area of ongoing investigation.
A documented effect of tesamorelin is a reduction in visceral adipose tissue in some study populations. Researchers have reported decreases in trunk fat measured by computed tomography alongside changes in lipid markers. The mechanism is thought to involve growth hormone-mediated lipolysis, though the precise contribution of direct versus indirect pathways is not fully resolved. Studies have generally examined defined groups over finite periods, so long-term outcomes are less well characterized. Findings have not been uniform across all trials.
== Society == In 2013, the US Congress passed the Recalcitrant Cancer Research Act, which mandated increased attention to certain recalcitrant cancers (cancers having a 5-year relative survival rate of less than 50%), including small cell lung cancer. That led to the National Cancer Institute supporting small cell-specific research.
Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second. Catalase is a tetramer of four polypeptide chains, each over 500 amino acids long. It contains four iron-containing heme groups that allow the enzyme to react with hydrogen peroxide. The optimum pH for human catalase is approximately 7, and has a fairly broad maximum: the rate of reaction does not change appreciably between pH 6.8 and 7.5. The pH optimum for other catalases varies between 4 and 11 depending on the species. The optimum temperature also varies by species.
What you are left with is a faceless mob, which is much harder to control". In addition, the orders stoked international concern; after the July 1985 announcement, the rand dropped to a record low, nearly matched in June 1986, and South African reserves were severely depleted. Nonetheless, the national state of emergency led to a sharp drop in reports of violence in the townships in subsequent months, in most accounts drawing the Vaal uprising to something approximating a conclusion; by 1987, wide-scale unrest persisted most severely in the KwaNdebele bantustan and later, in a different form, in Natal. However, there was continuous protest and intermittent violence across the country, including in Vaal, until and throughout the negotiations to end apartheid. The national state of emergency remained in place, renewed annually, until Botha's successor, F. W. de Klerk, announced in June 1990 that he would allow the decree to lapse everywhere but Natal.
Dwarfism can result from many medical conditions, each with its own separate symptoms and causes. Extreme shortness in humans with proportional body parts usually has a hormonal cause, such as growth hormone deficiency, once called pituitary dwarfism. Achondroplasia is responsible for the majority of human dwarfism cases, followed by spondyloepiphyseal dysplasia and diastrophic dysplasia.
Sources: en.wikipedia.org
Lipoprotein particles are organized by complex apolipoproteins, typically between 80 and 100 different proteins per particle, which can be recognized and bound by specific receptors on cell membranes, directing their lipid payload into specific cells and tissues currently ingesting these fat transport particles. These surface receptors serve as unique molecular signatures, which then help determine fat distribution delivery throughout the body. Chylomicrons, the least dense cholesterol transport particles, contain apolipoprotein B-48, apolipoprotein C, and apolipoprotein E (the principal cholesterol carrier in the brain) in their shells. Chylomicrons carry fats from the intestine to muscle and other tissues in need of fatty acids for energy or fat production. Unused cholesterol remains in more cholesterol-rich chylomicron remnants and is taken up from here to the bloodstream by the liver. VLDL particles are produced by the liver from triacylglycerol and cholesterol not used in the synthesis of bile acids. These particles contain apolipoprotein B100 and apolipoprotein E in their shells and can be degraded by lipoprotein lipase on the artery wall to IDL. This arterial wall cleavage allows absorption of triacylglycerol and increases the concentration of circulating cholesterol. IDL particles are then consumed in two processes: half is metabolized by HTGL and taken up by the LDL receptor on the liver cell surfaces, while the other half continues to lose triacylglycerols in the bloodstream until they become cholesterol-laden LDL particles.
The map passed the Maryland House of Delegates by a 99–37 vote on February 2, 2026, but died in the Maryland Senate after Senate President Bill Ferguson refused to hold a vote on the redistricting bill in the Senate. In March 2026, a spokesperson for Moore said he supported a compromise proposal that would create a referendum to amend the Constitution of Maryland to clarify that its rules about redistricting only apply to state legislative districts and not congressional districts. However, this compromise was rejected by Ferguson, who said the Senate would prioritize other issues with the remainder of the 2026 legislative session. The Maryland General Assembly adjourned sine die on April 13, 2026, without passing a new congressional redistricting map. In July 2026, leaders of the Maryland General Assembly announced that the legislature would convene for a special session on redistricting following the U.S. Supreme Court's decision in Louisiana v. Callais. During the special session, the General Assembly passed a constitutional amendment that would exempt Maryland's congressional districts from redistricting guidelines in the state constitution, which Moore signed into law in August 2026.
==== UPMC Salvator Mundi ==== UPMC Salvator Mundi International Hospital 75-bed private hospital in Rome, Italy, that is jointly owned by UPMC and Rome International Hospital Management Srl. UPMC owns a 50% stake in the hospital and leads its medical operations including having responsibility for selecting its medical director and chief operating officer.
Extensive research has been conducted to determine equivalence ratios comparing the relative potency of opioids. Given a dose of an opioid, an equianalgesic table is used to find the equivalent dosage of another. Such tables are used in opioid rotation practices, and to describe an opioid by comparison to morphine, the reference opioid. Equianalgesic tables typically list drug half-lives, and sometimes equianalgesic doses of the same drug by means of administration, such as morphine: oral and intravenous.
Alexander Bodkin at McLean Hospital, an affiliate of Harvard Medical School, began a collaboration with Somerset to develop delivery of selegiline via a transdermal patch in order to avoid the well known dietary restrictions of MAOIs. Somerset obtained FDA approval to market the patch for depression in 2006. Similarly, the orally disintegrating tablet (ODT) form of selegiline, marketed under the brand name Zelapar, was approved for Parkinson's disease in the United States in 2006 and in the European Union in 2010. Binding to and agonism of the trace amine-associated receptors (TAARs) as the mechanism responsible for the MAE effects of selegiline and related MAEs like PPAP and BPAP was first suggested in the early 2000s following the discovery of the TAARs. Activation of the TAAR1 as the mechanism of the MAE effects was first clearly substantiated in 2022.
Sources: en.wikipedia.org
9 May A record annual increase in atmospheric CO2 is reported from the Mauna Loa Observatory in Hawaii, with a jump of 4.7 parts per million (ppm) compared to a year earlier. A cubic millimetre of the human brain is mapped at nanoscale resolution by a team at Google. This contains roughly 57,000 cells and 150 million synapses, incorporating 1.4 petabytes of data. A study in Physical Review Letters concludes that the black hole in VFTS 243 likely formed instantaneously, with energy mainly expelled via neutrinos. This means it would have skipped the supernova stage entirely. An analysis of ocean protection for the global conservation target to protect at least 30% of the ocean by 2030 (30 by 30), finds around a quarter of marine protected area (MPA) coverage is not implemented, and one-third is incompatible with the conservation of nature due to the occurrence of highly destructive activities. According to the study, indicators of MPA quality, not only coverage, are needed. On 11 June, a study finds MPAs' effectiveness is not determined by any specific governance approaches or incentives, but the combination of many different integrated incentives. 10 May – A series of solar storms and intense solar flares impact the Earth, creating aurorae at more southerly and northerly latitudes than usual. 13 May – OpenAI reveals GPT-4o, its latest AI model, featuring improved multimodal capabilities in real time. 15 May Astronomers report an overview of preliminary analytical studies on returned samples of asteroid 101955 Bennu by the OSIRIS-REx mission.
Cl2C=CHCl + KH → ClC≡CCl + KCl + H2 A trace of methanol is required. It has also been generated (and used in situ) using lithium diisopropylamide under anhydrous conditions as well as potassium hydroxide.
==== 5α-Reductase and androgenicity ==== Testosterone can be robustly converted by 5α-reductase into DHT in so-called androgenic tissues such as skin, scalp, prostate, and seminal vesicles, but not in muscle or bone, where 5α-reductase either is not expressed or is only minimally expressed. As DHT is 3- to 10-fold more potent as an agonist of the AR than is testosterone, the AR agonist activity of testosterone is thus markedly and selectively potentiated in such tissues. In contrast to testosterone, DHT and other 4,5α-dihydrogenated AAS are already 5α-reduced, and for this reason, cannot be potentiated in androgenic tissues. 19-Nortestosterone derivatives like nandrolone can be metabolized by 5α-reductase similarly to testosterone, but 5α-reduced metabolites of 19-nortestosterone derivatives (e.g., 5α-dihydronandrolone) tend to have reduced activity as AR agonists, resulting in reduced androgenic activity in tissues that express 5α-reductase. In addition, some 19-nortestosterone derivatives, including trestolone (7α-methyl-19-nortestosterone (MENT)), 11β-methyl-19-nortestosterone (11β-MNT), and dimethandrolone (7α,11β-dimethyl-19-nortestosterone), cannot be 5α-reduced. Conversely, certain 17α-alkylated AAS like methyltestosterone are 5α-reduced and potentiated in androgenic tissues similarly to testosterone. 17α-Alkylated DHT derivatives cannot be potentiated via 5α-reductase however, as they are already 4,5α-reduced.
==== Molecular fingerprints ==== A molecular fingerprint is a binary vector, where each position corresponds to a specific molecular property. In this representation, a given position X may encode the presence or absence of a particular substructure, with '1' indicating presence and '0' indicating absence. Various types of molecular fingerprints exist, including PubChem CACTVS fingerprints, Klekota-Roth fingerprints, MACCS fingerprints, and Extended-Connectivity Fingerprints (ECFP). A molecular fingerprint can be deterministically computed from a given molecular structure. Different molecular structures may yield the same molecular fingerprint.
Sources: en.wikipedia.org
No. It is a peptide that acts upstream of growth hormone release, while growth hormone is the hormone itself. The two differ in size, in receptor, and in how the body clears them.
It blocks the amino-terminal degradation step that limits native GHRH. The addition extends how long the peptide survives in plasma without removing its ability to activate the receptor.
The chain contains 44 amino acid residues. It matches the human GHRH(1-44) sequence apart from the amino-terminal modification.
It is a laboratory-made peptide that mimics growth hormone-releasing hormone. It prompts the pituitary gland to release growth hormone and has been studied mainly in adults with HIV-associated lipodystrophy.